# Everything you need to know about "the merge"

## Merge consists of following components
1. Consensus upgrade from PoW to PoS
2. `Eth1Data` follow distance cut
3. `BEACONBLOCKROOT` opcode
4. Validator withdrawals
5. Merge eth1 chain into beacon chain

### Quick Merge (i.e. Consensus Swap)

In current discussions, quick merge is 1.) Although ideally 1-2.) can go together as 2.) is not too complex and involves only beacon chain work. It would make sense to deploy 3-4.) at once 3-6 months in later hard fork.

### Full Merge

Full merge is 1-5.) all together. With 5.), it requires infra to provide application chain history beyhond WS period. There will also be EVM and JSON-RPC changes. The complexity dramatically increases here.

### References
Quick merge:
- https://notes.ethereum.org/m9IX3OkkTveXCCOSzGkUiw
- https://github.com/ethereum/eth2.0-specs/pull/2257

Full merge:
- https://hackmd.io/QFm6Ih_-Si6_kSLCWTZQyw?view (Draft)
- https://github.com/ethereum/eth2.0-specs/pull/2229

Research posts:
- [Strawman proposal](https://notes.ethereum.org/E62tBuJWRyOQNwixuPOAwQ)
- [The eth1 -> eth2 transition](https://ethresear.ch/t/the-eth1-eth2-transition/6265)
- [What does a Miner revolt look like?](https://medium.com/coinmonks/what-does-a-miner-revolt-look-like-a99216fe270e)
- [High confidence on single block confirmation](https://ethresear.ch/t/high-confidence-single-block-confirmations-in-casper-ffg/8909)